1. Field of the Invention
This invention relates generally to automotive fluid systems and methods of use and more particularly to a transmission fluid exchange system and method of use.
2. Description of Related Art
The following art defines the present state of this field:
Allen, U.S. Pat. No. 4,408,960 describes a pneumatic method and apparatus for causing the rapid recirculation of a liquid between a plurality of containers by adjusting the pressure of a gas exerted within each of said containers to super-atmospheric, atmospheric and sub-atmospheric pressures, thereby avoiding the passing of the liquid through a mechanical flow-inducing pump. The containers are connected to each other by means of a liquid circulation system comprising a circulation conduit which includes a work station. A filled fist container is subjected to super-atmospheric pressure to force the liquid into the circulation system while a second empty container is subjected to sub-atmospheric pressure to suck the liquid from the circulation system. After each container is empty and before it is subjected to sub-atmospheric pressure, for refilling purposes, it is exposed to atmospheric pressure to release the elevated pressure therefrom. The circulation system preferably incorporates a bypass conduit including a liquid replenishment tank and/or means for adjusting the temperature of the liquid.
Viken, U.S. Pat. No. 5,318,080 describes fluid changing in an automatic transmission by opening the cooler line and draining used fluid, at the flow of normal circulation, out of the cooler line from the transmission into a drain receptacle for receiving used fluid and simultaneously supplying fresh fluid, from a pressurized supply receptacle, into the cooler return line to the transmission at a similar controlled rate that is equal or greater than the rate of flow of the used fluid into the drain receptacle.
Knorr, U.S. Pat. No. 5,415,247 describes an automotive fluid exchange system wherein new fluid (such as power steering fluid) is simultaneously exchanged with the used fluid. First and second fluid conduits having first and second pumps disposed therein, respectively, provide the passageway between an engine compartment and a container for the new and used fluid, respectively. The two pumps are selectively actuatable by a respective, conventional toggle switch. Conventional jumper cables provide the power supply means to drive the pumps.
Payne, U.S. Pat. No. 5,427,505 describes an apparatus for extracting and injecting liquid coolant from and into a reservoir for an engine cooling system. The apparatus includes a storage tank for the liquid coolant, and an air pressure system for selectively applying fluid pressure to the tank either above or below atmospheric pressure. A hose connects the tank to the engine cooling system reservoir through a double shut-off-type coupling. One part of the coupling is connected to the reservoir, and the other, to the end of the transfer hose each having its own independent shut-off valve. When the coupling is connected, the valves in both components are opened and conversely when the coupling is disconnected, the valves automatically close.
Taguchi, U.S. Pat. No. 5,520,518 describes a method of transferring fluent material transferring the material from a first pressure tank to a fluent material transfer destination by supplying compressed gas to the first tank through a compressor. The compressed gas is retained in the first tank for reuse. Additional fluent material is drawn into a second pressure tank and is transferred therefrom to the fluent material transfer destination by supplying the compressed gas from the first pressure tank to the second pressure tank through the compressor. The compressed gas is further retained in the second pressure tank transferring fluent material from the first pressure tank. As the compressed gas is emptied from each tank to the other tank, additional fluent material is drawn into that tank. The cycle can be repeated on a continuous basis to transfer large quantities of fluent material.
Evans, U.S. Pat. No. 5,738,499 describes a fluid delivery/extracting device for extracting fluid from and delivering fluid to a reservoir of a vehicle. The device includes a cylindrical body formed from a tube, a bottom member and a top member. The top member comprises an annular member and a closure which closes the annular member. A pair of fittings extending through the closure, one of which has a portion extending below the closures top surface. A dip tube is applied to the this fitting and extends nearly to the bottom of the container. A first hose extends from the first fitting outer portion to a reservoir to be filled or emptied and is sufficiently long to extend to the bottom of the reservoir. A second hose extends from the second fitting and is connectable to any vacuum port of a vehicle if the device is to be used to empty the reservoir, or to a supply of pressurized air, if the device is to be used to fill the reservoir. The device makes it fairly simple to extract fluid from and deliver fluid to even hard to reach reservoirs, and reservoirs which are filled with highly viscous fluids.
Dixon et al., U.S. Pat. No. 5,806,629 describes a fail-safe transmission service machine allowing old ATF to be pumped out of a transmission while the vehicle engine runs, and responsively pumps a matching volume of new ATF into the transmission so that dry running of the transmission can not occur. If the supply of new ATF runs out or if power to the service machine is interrupted, the machine reverts to closed loop fluid circulation for the transmission. A hydraulic rectifier provides for universal connection of hoses between the transmission cooler fluid circulation loop of the vehicle and the service machine. An alternative embodiment of the machine allows for similarly fail-safe exchange of power steering fluid from a vehicle, and replacement of the old fluid with new power steering fluid.
Dixon et al., U.S. Pat. No. 5,853,068 describes an automotive fluid service machine for changing fluids such as automatic transmission fluid, power steering fluid, and engine coolant, including a cabinet with a unitary integral fluid reservoir defined by a lower portion of the machine cabinet. This lower cabinet portion which integrally defines the fluid reservoir also provides a machinery deck to which the components of the machines are mounted. A cap portion of the cabinet provides a cavity for protecting the components mounted to the machinery deck and also provides a control panel for the machine in addition to providing fluid fill and drainage basins improving the convenience and safety of use for the machine. The safety of a service area is improved by the machine because a very low center of gravity for the machine reduces the risk of tipping of a machine and of spilling fluids. Thus, environmental concerns from such spills as well as the risk of personnel slips and falls on spilled fluids are reduced.
Dixon, U.S. Pat. No. 6,035,902 describes a fail-safe service machine for the power steering system of automotive vehicles including a pair of pumps each driven by electrical power from a vehicle under service, and a suction/delivery probe extending into the power steering system reservoir of the vehicle, both to remove old power steering fluid, and to simultaneously deliver new power steering fluid.
Rome et al., U.S. Pat. No. 6,062,275 describes an apparatus and method of replacing old fluid in a transmission system by feeding clean fluid into the system from a clean fluid tank using a pump and draining the old fluid into a waste tank and using a processor to monitor the clean fluid pressure in the clean tank and the old fluid pressure in the waste tank and adjusting the pump""s speed using the processor such that the old fluid is drained at substantially the same rate as the clean fluid is fed.
Rome et al., U.S. Pat. No. 6,247,509 describes and apparatus and method of replacing old fluid in a transmission system by feeding clean fluid into the system from a clean fluid tank using a pump and draining the old fluid into a waste tank and using a processor to monitor the clean fluid pressure in the clean tank and the old fluid pressure in the waste tank and adjusting the pump""s speed using the processor such that the old fluid is drained at substantially the same rate as the clean fluid is fed.
Evans, U.S. Pat. No. 6,286,626 describes an automated system for changing the motor oil in an engine. The system includes a drain plug having a plurality of channels coupled with tubing that extends to a reversible pump. Tubing extends from the pump to both a used oil container and a new oil container. Check valves positioned at the entrance of each container restrict flow so the oil can flow only to the used oil container and only flows from the new oil container. Preferably, both containers are located in the trunk of the vehicle for easy access. In use, the pump is engaged to draw the used motor oil from the engine into the used oil container. Next, the pump is reversed to draw fresh oil from the new oil container into the engine.
Viken, U.S. Pat. No. 6,378,657 describes fluid changing in an automatic transmission by opening the cooler line and draining used fluid, at the flow of normal circulation, out of the cooler line from the transmission into a drain receptacle for receiving used fluid and simultaneously supplying fresh fluid, from a pressurized supply receptacle into the cooler return line to the transmission at a similar controlled rate that is equal or greater than the rate of flow of the used fluid into the drain receptacle.
Betancourt et al., U.S. Pat. No. 6,382,271 describes an apparatus and method of replacing old fluid in a transmission system by feeding clean fluid into the system from a clean fluid tank using a pump and draining the old fluid into a waste tank and using a processor to monitor the clean fluid pressure in the clean tank and the old fluid pressure in the waste tank and adjusting the pump""s speed using the processor such that the old fluid is drained at substantially the same rate as the clean fluid is fed.
The prior art teaches the use of transmission fluid replacement systems, but does not teach a system that may be installed into one of the coolant lines of the transmission without knowing direction of flow, and does not teach a closed and sealed system that forces new replacement fluid into the transmission by both suction from the draining spent fluid and by pressure of displaced air in a sealed spent fluid container. The present invention fulfills these needs and provides further related advantages as described in the following summary.
The present invention teaches certain benefits in construction and use which give rise to the objectives described below.
A spent transmission fluid is drained from a transmission and replaced with new fluid. The process occurs while the transmission is operating so that the transmission""s converter forces the spent fluid into a spent fluid container, while air, displaced by the entering spent fluid, is forced into a second container holding a new replacement fluid. The second container is thereby pressurized and the new fluid is thus forced through an interconnecting conduit line into the dipstick tube of the transmission so as to replace the spent fluid flowing out. The spent fluid leaving the transmission causes suction to appear at the dipstick tube which sucks the new fluid into the transmission. To assure that this suction is maintained, the dipstick tube is sealed so that the system is closed allowing hands free operation. A flow directing device is used to assure proper fluid flow from the transmission or from the transmission""s cooler.
A primary objective of the present invention is to provide an apparatus and method of use of such apparatus that provides advantages not taught by the prior art.
Another objective is to provide such an invention capable of moving fluids between containers and the transmission system in such a manner that no exterior pump, other than the transmission pump, is required.
A further objective is to provide such an invention capable of quick and easy change of transmission fluid without excessive skill or supervision.
A further objective is to provide such an invention capable of system self pressurization for replacing transmission fluid.
A still further objective is to provide such an invention wherein the spent transmission fluid may be taken directly from the transmission line or from a transmission fluid cooler line without the necessity for checking in which direction the fluid is flowing.
A still further objective is to provide such an invention capable of replacing transmission fluid without spills and other potential damage to the environment because it is a closed and sealed system.
A still further objective is to provide such an invention capable of replacing transmission fluid without the aid of an external pump.
A still further objective is to provide hands free operation so that the fluid is less likely to come into contact with an operators skin.
Other features and advantages of the present invention will become apparent from the following more detailed description, taken in conjunction with the accompanying drawings, which illustrate, by way of example, the principles of the invention.